Bathroom scale construction



Dec. 29, 1953 J. c. SUTTON BATHROOM SCALE CONSTRUCTION 2 Sheets-Sheet 1 Filed Jan. 7, 1947 J. C. SUTTON BATHROOM SCALE CONSTRUCTION Dec; 29, 1953 2 Sheets-Sheet 2 Filed Jan. '7, 1947 Patented Dec. 29, 1953 UNITED STATES PATENT OFFECE 2,664,287 BATHROOM SCALE CONSTRUCTION John 0. Sutton, Rockford assignments; to

Ill., assignor, by mesne Cellusuede Products, Inc.,

Rockford, 111., a, corporation ofIllinois Application January 7, 1947, Serial No. 720,577 11 Claims. (01. 265-71) e um engagement onrthe base and under the plat form but they were objectionable because of their high cost and heavy weight and also because of the danger of breakage if the scale was dropped accidentally or was used too roughly. It is, therefore, the principal object of my invention to provide wishbone shaped levers made of seamless steeltubing bent to the desired shape and having hanger members inserted and suitably secured inthe ends, whereby to make for a low cost construction and one that is lighter, stronger, and substantially non-breakable. The end inserts are of a form to provide fulcrums in a plane in the correct upwardly offset relationship to the end portions of the levers on which the knife edge projections of the platform are arranged to rest, so that the desired close accuracy of weighing is more easily obtained in the quantity production of scales than with cast levers on which the knife edges are machined. Incidentally, the tubingused for the body portions of the levers is of cylindrical form and I, therefore, obtain point contacts between the levers and the knife edge projections on the platform, as distinguished from the line contacts provided with the earlier constructions, thus making for easier operation and closer accuracy in weighing. Moreover, this improved result is obtained by virtue of my improved construction without any machining operations on the levers, whereas the cast levers had to be accurately machined toprovide abutments for the platform legs, t

A further improvement provided in accordance with my invention is the use of a stamped elongated sheet metal yoke member which has a hook portion on the middlethereof in a planeat right angles to the plane of the yoke pivotally connected to the middle cross-portion of the small lever, said yoke also having knife edges on the ends thereof having point contacts on top of the arms ofthe large lever intermediate the ends thereof for transfer of that part of the load carried by the small lever to the large lever with minimum frictional drag on the easy operation of the scale, with resultant closer accuracy in weighing. v t I The invention is illustrated in the accompanying drawings, in which Fig. 1 is a phantom side view of a bathroom scale showing in full lines the lever mechanism with which my invention is particularly concerned and showing most of the rest of the scale in dotted lines;

Fig. 2 is a phantom top view of the scale showing the lever mechanism in full lines in plan;

Fig. 3 is a cross-section on line 3-3 of Fig. 2;

Fig. 3a is a cross-section similar to Fig. 3 but illustrating the use of solid rod material instead ofsteel tubing; I

Fig. 4 is an enlarged fragmentary sectional detail on line 4-4 of Fig. 3, and

Fig. 5 is a fragmentary illustration, in side e1e-' vation, corresponding to a portion of Fig. 1, but showing an alternative construction.

Similar reference numerals are applied to cor responding parts throughout the views.

Referring mainly to Figs. 1 to 4, the reference numeral 6 designates the generally rectangular sheet metal base of a bathroom scale and 1 the generally rectangular sheet metal platform supported on said base through the medium of the lever mechanism of my invention, indicated generally by the reference numeral 8. The latter, generally speaking, consists of a small U-shaped spider or wishbone lever 9, and a large V-shaped spider or wishbone lever ID, the two levers being interconnected by a yoke I I. Itis common practice to fulcrum the large lever at one end on the base, and to support the other end of the lever on a coiled tension spring, like that indicated at I2, which is suitably suspended in the upwardly projecting front end or housing portion 13 of the base, usually by means of a screw [4 and adjusting nut I5, so that the scale can be set back to zero if it gets out of adjustment. The small lever is usually supported at one end on the base and at its other end on the large lever so as to transfer its load to the large lever, the platform being supported at the front end on the small lever and at the rear end on the large lever. Two arms [6 project upwardly from the front corners of the base to support the lever 9, and two arms I 1 project upwardly from the rear corners of the base for support of the lever 10. Two legs l8 project downwardly from the corners of the front end of the platform to rest on the lever 9, and two legs {9 project downwardly from the corners of the rear end of the platform to rest on the lever Hi. Any suitable or preferred weight indicating means may be provided, as, for example, a dial 20 rotatab-ly mounted in and visiblethrough a window in the top of the housing l3 and operable by a pinion 2t meshing with, a rack 22 suitably guided in the housing for reciprocatory movement vertically and resting by means of its lower end portion 23 on the front end of the lever lil, said rack being arranged to gravitate in proportion to the deflection of the levers 9 and I under load.

In accordance with my invention, the spiders or levers 9 and it, instead of being of solid, heavy, cast iron construction, as heretofore, have the main body portions 29 and 30 thereof formed from single lengths of seamless steel tubing, of circular section, as indicated in Figs. 1 and 3, the tubular body 29 being bent to U-shape to provide parallel arms 3| connected by a cross portion 32, and the tubular body 30 being bent to V-shape and providing diverging arms 33 extending from the crotch portion 34, the extreme end portions 35 of the arms 33 being bent into parallelism and longitudnal alignment with the arms 3|, as shown. This construction offers many advantages: it is cheaper than machined castings; it is lighter; it has greater strength and is much more durable, and the rounded or cylindrical form of the tubing makes for point contact of knife edges resting thereon, as will soon appear. The rounded or cylindrical form of the tubing makes for easy working pivotal connections also at [2 where the hooked lower end of the spring 12 is attached to the front end of lever l0, and at 38 where the yoke H is attached to the rear end of lever 9. The intermediate portions 39 of the arms 33 are bent upwardly out of the plane of the lever [B into a plane above but parallel to the plane of the crotch portion 34 and end portions 35, as best appears in Fig. 1, to bridge over the rear portion of lever 9 and support the end portions 3i of the yoke II. The middle portion of the yoke ii projects downwardly and this downwardly reaching portion is bent to form a hook 38 that is arranged to be pivotally attached to the cross portion 32 of lever 9. All of the bends described on the levers can be made between dies at a small fraction of the cost involved in machining a pair of cast levers of the old design used heretofore so commonly in bathroom scales. When the spiders or levers are made from single lengths of steel rod material of circular section, as indicated at 9' and ill in Fig. 3a, the same bends are needed and can be made between the same dies as required in the tubing construction. Lever 9 has a pair of steel or cast iron members 39 inserted in the open ends of the arms 3| which provide the hook shaped hanger portions 49 for fulcrum engagement on arms It. In like manner, similar members 4| inserted in the open ends of the arms 33 of lever l0 provide hangers 42 for fulcrum engagement on arms IT. The inserts 39 and 4| may be secured in any suitable or preferred manner, as by welding, brazing, or soldering, silver solder being indicatedm the angular groove 43 in the reduced cylindrical shank 44 in Fig. 4. They can be made at low cost to the desired accuracy and they provide the desired accurate upwardly offset relationship of the fulcrum points 45 relative to the center lines of the tubular end portions of the levers 9 and I9 that is essential for accurate weighing. The fulcrum members, in case solid rod material is used for the spiders or levers, may either be inserted in holes made in the ends or they may be applied There doubly important in this scale because of the fact that the knife edges 41 on the lower ends of legs 18 and 19 have point contact, as indicated at 49, directly on top of the tubular end portions of said levers, as shown in Fig. 1. The levers 9 and I!) are shown in Fig. 1 in the mid position of deflec tion under load corresponding approximately to about lbs. loading, and it will be noticed that in this position all of the fulcrum points 45 and 48 are in the same horizontal plane. The knife edges l'i moves downwardly about in 125 lbs. loading, speaking, of course, of dimensions in the actual full size scale, to reach the position illustrated in Fig. 1, and they move downwardly about farther with an additional 125 lbs. loading. This is the maximum load for which the scale is designed. Hence, the angularity of movement of the levers 9 and 10 both ways from the mean position is small enough to avoid too much inaccuracy in weight indications at either extreme, the closest accuracy being in the region of the mean position.

In Fig. 5, I have shown a modified or alternative construction in which the fulcrum insert 39', in the end portion of the tubular lever 9' is like the inserts 39 and ti, but the fulcrum point 45' is formed by the apex of a V-shaped projection 40' which cooperates with a V-notch 46 in the upper end of the arm it that extends upwardly from the base 5. The platform 1 is supported on two levers, one of which is lever 9, in the same way as in the other construction 7 described, namely, by means of four legs, one of which is shown at l8. This construction operates like the other one and affords the same advantages.

It is believed the foregoing description conveys a good understanding of the objects and advantages of my invention. The appended claims have been drawn to cover all legitimate modifications and adaptations.

I claim:

1. As an article of manufacture, a lever for fulcrum engagement on the base of a bathroom scale and for support of the platform of said scale, said lever comprising a body made substantially entirely of a single continuous length of stiff steel tubing bent substantially to forked form, the ends of the arms of the forked body being left open, and two fulcrum members comprising bodies having reduced elongated mounting, portions entered and nonrotatably secured in the open ends of said arms.

2. As an article of manufacture, a lever for fulcrum engagement on the base of a bathroom scale and for support of the platform of said scale, said lever comprising a body made substantially entirely of a single continuous length of stiff steel tubing bent substantially to forked form, the ends of the arms of the forked body being left open, and two fulcrum members comprising bodies having reduced elongated mounting portions entered the open ends of said arms, the bodies of both of said fulcrum members being formed to provide knife edge fulcrum bearing portions offset upwardly the same distance 7 ter lines of the ends of the arms of the forked body.

3. In combination, in a bathroom scale con-. struction in which a platform is supported by lever mechanism on a base, a pair of wishbone levers, one of which has a V-shaped body of substantially twice the overall length of the body of the other which is U-shaped, the V-shaped and U-shaped bodies being both bent from single lengths of stiff tubing material of circular secand nonrotatably secured in relative to the cention and substantially uniform diameter and said bodies being-disposed in overlapped relation and facing in opposite directions in substantially the same horizontal plane, the arms of the V-body being bent upwardly intermediate their ends to bridge over the cross-portion of the U-body, and a transverse yoke member having. knife-edged end portions resting with point contacts on top of the upwardly bent portions of the arms of the V-body and having a depending hook portion on the middle thereof hooked under the cross-portion of the U-body.

4. As an article of manufacture, a lever for fulcrum engagement on the base of a bathroom scale and for support of the platform of said scale, said lever comprising a body made substantially entirely of a single continuous ngth of stiff tubing material of circular section and substantially uniform diameter bent substantially to forked form and two fulcrum members secured onto the ends of the arm of the forked body.

5. As an article of manufacture, a lever for fulcrum engagement on the base of a bathroom scale and for support of the platform of said scale, said lever comprising a body made subtantially entirely of a single continuous length of stiff tubing material of circular section and substantially uniform diameter bent substantially to forked form and two fulcrum members secured :7

onto the ends of the arms of the forked body, the bodies of both of said fulcrum members being formed to provide knife edge fulcrum bearing portions offset upwardly the same distance relative to the center lines of the ends of the arms of the forked body.

6. In combination, in a bathroom scale construction in which a platform is supported by lever mechanism on a base, a pair of wishbone levers one of which has a V-shaped body of substantially twice the overall length of the body of the other which is U-shaped, the V-shaped and U-shaped bodies being both bent from single lengths of stiff steel tubing of circular section and substantially uniform diameter and said bodies being disposed in overlapped relation and facing in opposite directions in substantially the same horizontal plane, the arms of the V-body being bent upwardly intermediate their ends to bridge over the cross-portion of the U-body, a transverse yoke member having knife-edged end portions resting with point contact on top of the upwardly bent portions of the arms of the V-body and having a depending hook portion on the middle thereof hooked under the cross-portion of the U-body, and fulcrum members mounted in the open ends of the arms of the V and U bodies for fulcrum support of said levers on the base.

7. In combination in a bathroom scale construction, a base having an upwardly projecting supporting arm having a knife edge bearing on the upper end, a platform supporting lever member comprising a body of cylindrical tubing which is of substantially uniform diameter havin a fulcrum member inserted in the open end and resting on said knife edge bearing for support, and a weighing platform having a downwardly projecting supporting leg having a knife edge on the lower end resting with point contact on the cylindrical body of said lever.

8. In combination in a bathroom scale construction, a base having an upwardly projecting supporting arm having a knife edge bearing on the upper end, a platform supporting lever member comprising a body of cylindrical tubing which all) is of substantially uniform diameter having a fulcrum member comprising a body inserted in the open end and resting on said knife edge bearing for support, and a weighing platform having a downwardly projectin supportin leg having a knife edge on the lower end resting with point contact on the cylindrical body of said lever, the body of said fulcrum member being formed to provide knife-edge fulcrum bearing portions offset upwardly so that the lever member is under slung to a predetermined extent relative to the knife edge bearing.

9. In combination, in a bathroom scale construction in which a platform is supported by lever mechanism on a base, a pair of wishbone levers, one of which has a V-shaped body of substantially twice the overall length of the body of the other which is U-shaped, the V-shaped and U-shaped bodies being both bent from single lengths of stiff steel tubing of circular section and substantially uniform diameter and said bodies being disposed in overlapped relation and facing in opposite directions in substantially the same horizontal plane, the arms of the V-body being bent upwardly intermediate their ends to bridge over the cross-portion of the U-body, a transverse yoke member havin knife-edged end portions resting with point contacts on top of the upwardly bent portions of the arms of the V- body and having a depending hook portion on the middle thereof hooked under the cross-portion of the U-body, fulcrum members mounted in the pen ends of the arms of the V and U bodies providing fulcrum support for said levers on the base, and supporting legs for said platform having knife edges on the lower ends thereof resting with point contact on the tops of said wishbone levers.

19. In combination, in a bathroom scale construction in which a platform is supported by lever mechanism on a base, a pair of wishbone levers, one of which has a V-shaped body of substantially twice the overall length of the body of the other which is U-shaped, the V-shaped and U-shaped bodies being both bent from single lengths of stiff steel tubing of circular section and substantially uniform diameter and said bodies being disposed in overlapped relation and facing in opposite directions in substantially the same horizontal plane, the arms of the V-body being bent upwardly intermediate their ends to bridge over the cross-portion of the U-body, a transverse yoke member having knife-edged end portions resting with point contacts on top of the upwardly bent portions of the arms of the V-body and having a depending hook portion on the middle thereof hooked under the cross-portion of the U-body, fulcrum members having portions of the bodies thereof mounted in the open ends of the arms of the V and U bodies providing fulcrum support for said levers on the base, the bodies of said fulcrum members being formed to provide knife-edge fulcrum bearing portions offset upwardly so that said levers are underslung to a predetermined extent in relation to their fulcrum support on the base, and supporting legs for said platform having knife edges on the lower ends thereof resting with point contact on the tops of said wishbone levers.

11. In combination, in a bathroom scale construction in which a platform is supported by lever mechanism on a base, a pair of wishbone levers, one of which has a V-shaped body of substantially twice the overall length of the body of the other which is U-shaped, the V-shaped and U-shaped bodies being both bent from single lengths of stiff steel tubing of circular section and substantially uniform diameter and said bodies being disposed in overlapped relation and facing in opposite directions in substantially the same horizontal plane, the arms of the V-body being bent upwardly intermediate their ends to bridge over the cross-portion of the U-body, a transverse yoke member having knife-edged end portions resting with point contacts on top of the upwardly bent portions of the arms of the V- body and having 2. depending hook portion on the middle thereof hooked under the cross-portion of the U-body, and fulcrum members having portions of the bodies thereof mounted in the open ends of the arms of the V and U bodies for fulcrum support of said levers on the base, the bodies of said fulcrum members being formed to provide knife-edge fulcrum bearing portions offset upwardly so that said levers are underslung to a, predetermined extent in relation to their fulcrum support on the base.

JOHN C. SUTTON.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date Cary Oct. 22, 1918 Wetzel Nov. 1, 1927 Johnson Jan. 8, 1929 Vernet June 31, 1933 Weber et al. Oct. 6, 1936 King Aug. 27, 1940 Haferl Dec. 2, 1947 Hansen Oct. 4, 1949 

